Question

[blazincajun]

Hello,<br />I was wondering if anyone knows if there is any asteroids or comets that may collide with any of the other planets besides earth in the near future.<br /><br />I know that we have mapped most of the paths of these around earth, but what about the other planets.<br /><br />I saw what Jupiter looked like when the comet hit it, and I wanted to see what it looks like on the other planets.<br /><br />Thanks <div class="Discussion_UserSignature"> </div>

 

[brandbll]

Is the hubble the only thing that observed it well? <div class="Discussion_UserSignature"> <p><font size="3">You wanna talk some jive? I'll talk some jive. I'll talk some jive like you've never heard!</font></p> </div>

 

[yevaud]

No, there were numerous observations, both ground-based, and from various space-borne platforms.<br /><br /><i>Nearly every observatory in the world will be observing events associated with the impacts. These include Earth-orbiting telescopes (Hubble Space Telescope, International Ultraviolet Explorer, Extreme Ultraviolet Explorer), several interplanetary spacecraft (Galileo, Ulysses, and Voyager 2) and ground-based observatories located on every continent in the World including Antarctica.<br /><br />Plans for observations of the chemistry of Jupiter's atmosphere as it is affected by the collisions will be carried out in the ultraviolet, visible, near-infrared and radio wavelength regions. Because the predictions are uncertain, it is important to observe for all predicted species. Molecules containing eight different elements are reasonably expected to appear.<br /><br />Helium emission might be detected by the Extreme Ultraviolet Explorer and provide information about the amount of atmospheric heating in the upper atmosphere. Telescopes located in Hawaii, Texas, Chile, Australia and Russia will monitor near-infrared atmospheric chemistry. Ions of H3+ and H3O+ are observable near 3.5 microns and will be diagnostic of ionospheric processes.</i><br /><br />http://www.seds.org/sl9/factsheet.html <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[bioandy]

Just wondering if anyone knows how many Amature Astronomers there are world wide?<br /><br />And if you have any data (web post, statistics etc...) that could verify this number.<br /><br />Thanks

 

[tfwthom]

Well I don't know if anyone has a actual number but.....<br /><br />If you take:<br /><br />From S&T http://skyandtelescope.com/aboutsky/advertiserinfo/article_441_1.asp<br /><br />Reader Demographics<br /><br /><br />From Rate Card #47<br />Effective January 2006<br />Male: 95%<br />Female: 5%<br /><br /><br />Average age: 51 <br /><br />Married: 70%* <br /><br />Graduated from college or higher: 77% <br /><br />Professional/technical careers: 60%* <br /><br />Average household income: $94,400 <br /><br /><br /><br />--------------------------------------------------------------------------------<br /><br />40% have been involved in the hobby an average of 20+ years* <br /><br />26% have been involved less than 5 years* <br /><br /><br /><br />--------------------------------------------------------------------------------<br /><br />Subscribers classify themselves as beginners: 10%, amateurs: 49%, advanced amateurs: 38%, professionals: 3% <br /><br /><br /><br />--------------------------------------------------------------------------------<br /><br />Total paid circulation: 100,215 <br /><br />Rate base: 90,000 <br /><br />Pass-along readership: 0.7 <br /><br />Grand total readership: 170,365 <br /><br />*Simmons Research, Inc., June 1998 — all other data from Publisher's Subscriber Survey, May 2005, and ABC Publisher's Statement, June 2005. <br /><br />From Astronomy: http://www.astronomy.com/asy/objects/pdf/astronomy_2006rc(2).pdf<br /><br />Total paid circulation: 133,379<br /><br /><br /><br /><br />Figure I get both but since this doesn't include news stands, and this is only US sales over 300k so just guessing. 300,000 amateurs astronomers in the US sounds about right.<br /><br /><br /><br /> <div class="Discussion_UserSignature"> <font size="1" color="#3366ff">www.siriuslookers.org</font> </div>

 

[tfwthom]

My wife says I'm low balling the number. (she does this for a living)<br /><br />I still don't know where you could get any real numbers. <br /><br />Can't use club membership (not everyone belongs to a club) (even if they should) Can't use telescope sales (most have more then one scope) Can't use star party attendence (not eveyone goes to a star party) <div class="Discussion_UserSignature"> <font size="1" color="#3366ff">www.siriuslookers.org</font> </div>

 

[dina1943]

<p>I have a question that I hope someone can answer for me. Do planets explode? Like stars do?</p>

 

[dina1943]

do planets explode like stars do?

 

[nimbus]

<p>Planets are too inert to ever break down any more than superficialy, volcanicaly. &nbsp;Stars explode because at some point the two groups of forces (inward and outward) lose their equilibrium, resulting in the stars' usualy explosive disintegration.</p><p>&nbsp;Oops, I somehow didn't see the duplicate thread. &nbsp;Feel free to delete this.&nbsp;</p> <div class="Discussion_UserSignature"> </div>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>I have a question that I hope someone can answer for me. Do planets explode? Like stars do? <br />Posted by dina1943</DIV><br /><br />didn, Welcome to SPace.com</p><p>&nbsp;</p><p>You should only start one thread on a subject, not keep repeating it.</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[_Simon_]

<p>I was wondering if its been confirmed that Jupiter, Saturn and Uranus have solid crusts or if they only consist of gas in one form or another.</p><p>&nbsp;Thanks in advance! </p><p>&nbsp;//Simon </p> <div class="Discussion_UserSignature"> </div>

 

[origin]

Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>I was wondering if its been confirmed that Jupiter, Saturn and Uranus have solid crusts or if they only consist of gas in one form or another.&nbsp;Thanks in advance! &nbsp;//Simon <br />Posted by _Simon_</DIV><br /><br />The current theory is they have no crust.&nbsp; The density just gets high and high as you move to the center of the planets without a definitive surface. <div class="Discussion_UserSignature"> </div>

 

[_Simon_]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>I was wondering if its been confirmed that Jupiter, Saturn and Uranus have solid crusts or if they only consist of gas in one form or another.&nbsp;Thanks in advance! &nbsp;//Simon <br /> Posted by _Simon_</DIV></p><p>&nbsp;</p><p>So it would not be possible to land a vessle of any kind there? In theory that is. If I am not mistaken there were some kind of meteor which crasched into Jupiter some years ago. But if there is no crust - what did it hit? If Jupiter is made of gas wouldnt a meteor go right though it? Or would the gravity rip it apart?&nbsp; </p> <div class="Discussion_UserSignature"> </div>

 

[origin]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;So it would not be possible to land a vessle of any kind there? In theory that is. If I am not mistaken there were some kind of meteor which crasched into Jupiter some years ago. But if there is no crust - what did it hit? If Jupiter is made of gas wouldnt a meteor go right though it? Or would the gravity rip it apart?&nbsp; <br />Posted by _Simon_</DIV><br /><br />The comet pieces hit jupiter and the intense heat due to the friction with the gases essentially tore a hole in the atmosphere.&nbsp; These large features lasted for weeks before they dissapated.&nbsp; There are large storms on Jupiter that last for years.</p><p>edited to add:&nbsp; Look up shoemaker-levy, that is the comet that hit Jupiter.</p> <div class="Discussion_UserSignature"> </div>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>The comet pieces hit jupiter and the intense heat due to the friction with the gases essentially tore a hole in the atmosphere.&nbsp; These large features lasted for weeks before they dissapated.&nbsp; There are large storms on Jupiter that last for years.edited to add:&nbsp; Look up shoemaker-levy, that is the comet that hit Jupiter. <br />Posted by origin</DIV><br /><br />Technically, it was Shoemaker-Levy 9, the 9th comet that the team discovered.</p><p>If there is a rocky core inside Jupiter, you would be crushed by the pressure long before reaching it, so no a spacecraft cannot be landed there. IIRC, Galileo was plunged into Jupiter for destruction to avoid contaminating any of it's moons.</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[weeman]

Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;So it would not be possible to land a vessle of any kind there? In theory that is. If I am not mistaken there were some kind of meteor which crasched into Jupiter some years ago. But if there is no crust - what did it hit? If Jupiter is made of gas wouldnt a meteor go right though it? Or would the gravity rip it apart?&nbsp; <br />Posted by _Simon_</DIV><br /><br />Even if it consists entirely of gas, it is a massive planet, meaning it has very intense atmospheric pressure. Keep in mind that Jupiter is very large, the largest planet in the solar system. A full Earth could fit easily into its "Great Red Spot". Jupiter has an equatorial diameter of about 89,000 miles, meaning it has a radius of about 45,000 miles. The deeper you go towards the core, the more intense the pressure will become. <div class="Discussion_UserSignature"> <p> </p><p><strong><font color="#ff0000">Techies: We do it in the dark. </font></strong></p><p><font color="#0000ff"><strong>"Put your hand on a stove for a minute and it seems like an hour. Sit with that special girl for an hour and it seems like a minute. That's relativity.</strong><strong>" -Albert Einstein </strong></font></p> </div>

 

[Saiph]

<p>For a bit of a demonstration as to why a comet would hit and be destroyed even in a gas only planet...take a look at water.</p><p>Fill your tub, or sink with water.&nbsp; Dip your hand in...no real resistance right?&nbsp; Now, brace yourself, and with your hand rigid, SMACK the water with the palm of your hand...stings eh?&nbsp; Scale up to a belly flop at a pool if you want </p><p>Even a gas, if hit hard enough, fast enough, can exert very high forces as the pressure builds.&nbsp; Liquids are the same, only they do it faster.&nbsp; You do 'not' need a rigid surface to be stopped. </p> <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>

 

[MeteorWayne]

Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>For a bit of a demonstration as to why a comet would hit and be destroyed even in a gas only planet...take a look at water.Fill your tub, or sink with water.&nbsp; Dip your hand in...no real resistance right?&nbsp; Now, brace yourself, and with your hand rigid, SMACK the water with the palm of your hand...stings eh?&nbsp; Scale up to a belly flop at a pool if you want Even a gas, if hit hard enough, fast enough, can exert very high forces as the pressure builds.&nbsp; Liquids are the same, only they do it faster.&nbsp; You do 'not' need a rigid surface to be stopped. <br />Posted by Saiph</DIV><br /><br />Another good example is meteors and fireballs. They are destroyed in the upper reaches of the atmosphere where the air is far too thin to breath. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[3488]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'><font color="#ff0000">Technically, it was Shoemaker-Levy 9, the 9th comet that the team discovered.If there is a rocky core inside Jupiter, you would be crushed by the pressure long before reaching it, so no a spacecraft cannot be landed there. IIRC, Galileo was plunged into Jupiter for destruction to avoid contaminating any of it's moons. <br /> Posted by MeteorWayne</font></DIV></p><p><font size="2"><strong>That's correct Wayne, The Galileo Orbiter was deliberately de orbited into Jupiter to avaoid an miniscule, though not nil risk of the Galileo orbiter eventually, possibly after decades, maybe centuries or millenia later impacting Europa.</strong></font></p><p><font size="2"><strong>Also it is correct regarding the pressures. To all intents & purposes, Jupiter has no 'surface' as such, just a denser & denser atmosphere as one descends towards that possible core. It has also been suggested that there is a liquid hydrogen ocean under the point that the atmosphere becomes dense enough to support liquid hydrogen under high temperatures (not to be confused with the purported Metallic Hydrogen mantle surrounding the core, that generates the gigantic Jovian magnetosphere).</strong></font></p><p><font size="2"><strong>The Galileo Atmosphere probe that entered jupiter's atmosphere at the start of the primary mission in December 1995 expired approx 100 KM below the 1 Bar level or 200 KM below parachute deployment @ 24 Bars & 153 C (the parachute very nearly failed to open due to faulty wiring, so it was sheer luck the probe succeeded, one of several serious problems to dog the mission & threaten failure, though Galileo perservered).</strong></font></p><p><font size="2"><strong>Andrew Brown. </strong></font></p> <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[_Simon_]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>For a bit of a demonstration as to why a comet would hit and be destroyed even in a gas only planet...take a look at water.Fill your tub, or sink with water.&nbsp; Dip your hand in...no real resistance right?&nbsp; Now, brace yourself, and with your hand rigid, SMACK the water with the palm of your hand...stings eh?&nbsp; Scale up to a belly flop at a pool if you want Even a gas, if hit hard enough, fast enough, can exert very high forces as the pressure builds.&nbsp; Liquids are the same, only they do it faster.&nbsp; You do 'not' need a rigid surface to be stopped. <br /> Posted by Saiph</DIV></p><p>&nbsp;</p><p>Thank you for your very informative answer. It makes perfect sense. You guys are great!&nbsp;</p><p>&nbsp;</p><p>Cheers! </p> <div class="Discussion_UserSignature"> </div>

 

[3488]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'><font color="#ff0000">For a bit of a demonstration as to why a comet would hit and be destroyed even in a gas only planet...take a look at water.Fill your tub, or sink with water.&nbsp; Dip your hand in...no real resistance right?&nbsp; Now, brace yourself, and with your hand rigid, SMACK the water with the palm of your hand...stings eh?&nbsp; Scale up to a belly flop at a pool if you want Even a gas, if hit hard enough, fast enough, can exert very high forces as the pressure builds.&nbsp; Liquids are the same, only they do it faster.&nbsp; You do 'not' need a rigid surface to be stopped. <br /> Posted by Saiph</font></DIV></p><p><font size="2"><strong>Hi Saiph,</strong></font></p><p><font size="2"><strong>That's very true. Some water skiers who fall can get friction burns from the water. The Galileo Atmosphere probe for example hit the top of Jupiter's atmosphere @ 170,000 KPH / 106,000 MPH & endured 230 Gs as it slowed to approx 400 KPH / 250 MPH, before deploying the parachute (which happened 53 seconds late, but very nearly did not happen). </strong></font></p><p><font size="2"><strong>Andrew Brown. </strong></font></p> <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[weeman]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>For a bit of a demonstration as to why a comet would hit and be destroyed even in a gas only planet...take a look at water.Fill your tub, or sink with water.&nbsp; Dip your hand in...no real resistance right?&nbsp; Now, brace yourself, and with your hand rigid, SMACK the water with the palm of your hand...stings eh?&nbsp; Scale up to a belly flop at a pool if you want Even a gas, if hit hard enough, fast enough, can exert very high forces as the pressure builds.&nbsp; Liquids are the same, only they do it faster.&nbsp; You do 'not' need a rigid surface to be stopped. <br />Posted by Saiph</DIV><br /><br />That's a very good analogy </p><p>&nbsp;</p> <div class="Discussion_UserSignature"> <p> </p><p><strong><font color="#ff0000">Techies: We do it in the dark. </font></strong></p><p><font color="#0000ff"><strong>"Put your hand on a stove for a minute and it seems like an hour. Sit with that special girl for an hour and it seems like a minute. That's relativity.</strong><strong>" -Albert Einstein </strong></font></p> </div>